System and method for broadcasting web pages and other information

ABSTRACT

A system and method for interactive broadcast of Internet web pages, or the like, on dedicated downstream channels in a cable television system or the like facilitates hyperlinking by a user from a broadcast television program to a web page, or between web pages, for example. In one embodiment, each user&#39;s set top is programmed with channel mapping information that maps each hyperlink request to a particular channel and time where the requested information is being broadcast in a multiplexed information stream. In response to receipt of a hyperlink request from a user actuating a remote control button, mouse or keyboard, the set top tunes to the appropriate one of the downstream channels, and downloads the web page or other information. In one embodiment to facilitate picture-in-picture capability using a single tuner, the tuner in the set top briefly tunes away from the video program to the appropriate data channel for receiving the hyperlink information. After the information associated with the hyperlink is downloaded and stored in the set top, the tuner automatically tunes back to the video program. The user can then interact with the hyperlink content and continue watching TV simultaneously. Alternatively, a scaler application is provided in the headend that reduces the size of the video program or a content related web page, for example, so that they can then be combined at the headend in a picture-in-picture format.

PRIORITY CLAIM UNDER 35 USC 119 (e)

[0001] The present application claims the benefit, under 35 USC 119 (e),of U.S. Provisional Application Nos. 60/170,792 and 60/170,793, bothfiled Dec. 15, 1999.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a system and method forbroadcasting information, such as Internet web pages, over a networkeddistribution system, such as a cable television distribution system.

[0004] 2. Description of the Background Art

[0005] U.S. Pat. No. 5,961,603, issued Oct. 5, 1999, U.S. Pat. No.5,999,979, issued Dec. 7, 1999, and U.S. Pat. No. 6,049,539, issued Apr.11, 2000, all of which are hereby incorporated by reference, disclosesystems and methods for providing interactive access to an informationsource, such as the Internet, through a networked distribution system,such as a cable television distribution system. In a conventional cabletelevision distribution system, video programming originating fromremote and local sources is broadcast from a cable headend, through aplurality of downstream channels to a set top converter box (set top)located at each user's premises. The set top interfaces the receivedprogramming to the user's television or monitor, and includes a tunerthat is used to select the channel to be viewed, typically by receivingcommands from a remote control operated by the user. In the systemdisclosed in the '603 patent, a cable television user who is asubscriber to a special Internet access service, can access Internet webpages that are related to the present programming content of a cabletelevision channel being viewed by the user. This technique is referredto as CHANNEL HYPERLINKING. In addition, the user can “surf” theInternet in a conventional manner with this system.

[0006] In the preferred embodiment disclosed in the '603 patent, thecable television distribution system includes a number of modificationsfor processing hyperlinking requests from the users. First, at least oneupstream channel is provided between each user and the cable headend sothat a user can enter hyperlinking requests into their set top, andforward them to the cable headend for processing. The cable headendprocesses each request by accessing a hyperlink database containingURL's (web addresses) of programming-content related Internet web pages,and retrieving a URL that has been assigned to the channel that the useris viewing for the time period during which the request is made. Thecable headend then retrieves the web page from the Internet, or frommemory, with an Internet browser application located in the headend, anddownloads the web page to the user for viewing. As an example, the user,who may be viewing a television advertisement for a particular product,can thus hyperlink to a web page for that product with this system.

[0007] The preferred embodiment of the channel hyperlinking systemdisclosed in the '603 patent thus provides a convenient technique forenabling users to access additional information that is related to thecontent of the program they are currently viewing, by simply pressing abutton on their remote control. However, the preferred embodiment is notdesigned for use with cable systems that provide only one-waycommunication between the cable headend and the system users, since theupstream channel is necessary to send channel hyperlinking requests tothe headend.

[0008] Another feature that would be desirable in a channel hyperlinkingsystem is “picture-in-picture” capability, wherein a user cansimultaneously view both a broadcast television program and a contentrelated web page, for example, so that they can continue watchingtelevision while interacting with a channel hyperlink, or conducting anInternet session. For example, the television program could be a scaledimage within the web page, or vice versa. Picture-in-picture is easy toprovide in a two-tuner set top where one tuner receives the videoprogram, while the other tuner receives the channel hyperlink data.However, the typical set top only has a single in-band tuner that can beused for either video or data.

SUMMARY OF THE INVENTION

[0009] The present invention addresses the foregoing issues throughprovision of a networked distribution system that facilitates channelhyperlinking capabilities without the need for upstream channels, andalso provides picture-in-picture capability without the need formultiple tuners. In a first preferred embodiment of the invention, thesystem is designed to provide continuous broadcast of Internet webpages, and other information, on one or more downstream channels. Thissystem facilitates Internet access, including channel hyperlinking,without the requirement that information or hyperlinking requests besent through an upstream channel for processing by the cable headend.Instead, hyperlink requests are processed in each user's set topconverter box by a terminal processor that is programmed to identify adownstream channel on which the requested information is beingbroadcast, and instruct the set top's tuner to switch to that channel.

[0010] More particularly, to implement this embodiment of the presentinvention, the cable headend is modified to broadcast Internet web pagesor other information on one or more downstream channels. Preferably, amultiplexing scheme is employed wherein each downstream channelbroadcasts information for multiple web pages, or the like, in acarouseled manner in which multiple, repeating time slots are provided,one for each web page or groups of web pages to be broadcast. Themultiplexing arrangement greatly increases the effective bandwidth ofeach channel, and provides for infinite scalability so that any numberof web pages or other information may be continually broadcast over alimited number of channels. This is made possible by the fact that mostweb pages contain a limited amount of information, the majority of whichis static. It is thus feasible to transmit the information for each pageon a periodic basis, e.g., once every 10 seconds or so, with the onlyconsideration being the amount of time that a user will be willing towait for the requested information to arrive.

[0011] The set top's terminal processor recognizes Internet access andchannel hyperlink requests that are directed to any of the broadcast webpages. More particularly, the terminal processor accesses a channelmapping database in the set top that maps each request received from auser via a remote control, keyboard or other input device, to theappropriate downstream channel and time slot therein, which isidentified by a packet identifier (PID), on which the requestedinformation is being broadcast. Using the PID information, the terminalprocessor instructs the set top's tuner to switch to the designatedchannel, and downloads the web page information for display on theuser's television. To facilitate efficient downloading of the requestedchannel hyperlink content, the terminal processor preferably waits untilthe data of interest appears in the carousel at the headend, and theninstructs the set top's tuner to switch away from the television channelthat a user is currently viewing. The requested content is downloadedinto a cache in the set top, and the tuner is then instructed to switchback to the original program channel. In this manner, the amount of timethat the user cannot watch their program during downloading of therequested hyperlink content is minimized.

[0012] The foregoing arrangement also facilitates picture-in-picturecapability without requiring the provision of two tuners in the set top.To achieve this, the terminal processor runs any suitable displaymanager program having picture-in-picture capability, which accesses thehyperlink content stored in the set top's cache, and overlays thecontent over the television program, or vice versa. The user can thensimultaneously conduct an Internet session and continue watching thetelevision program, for example.

[0013] There are a number of other changes that are preferably made inthe headend to facilitate accessing of the web pages or otherinformation being broadcast on the downstream channels. The first changeinvolves the data encoding (e.g., MPEG 1 or MPEG 2) that is employed toencode the web page image data to reduce bandwidth requirements. Intwo-directional channel hyperlinking where the headend responds to ahyperlink request by downloading the content related information on adownstream channel, it is only necessary to transmit a full frame ofimage data, known as an I-frame, at the beginning of the transmission,and when the next image frame differs completely from the previous imageframe. Otherwise, it is adequate if only differences between one imageframe and the previous frame are transmitted. These are referred to asdifference frames, and substantially reduce the bandwidth required fortransmitting the information. However, in one-way channel hyperlinking,the headend does not have knowledge when a viewer has requested ahyperlink. It is thus necessary to send full I-frames every second or soto insure that set tops that tune to the channel get an I-frame within ashort enough time period that the viewer is satisfied with the service.Thus, for any channel that is designated by the system to be a broadcastchannel for web pages, the encoder is programmed to send full I-framesfrequently enough that a viewer who is just tuning in, will not have towait long for receipt of the web page data.

[0014] In another preferred embodiment of the present invention, singletuner picture-in-picture capability is provided in an alternative mannerby formatting, combining and encoding the information for both datastreams in the headend, and transmitting the combined data on one of thedownstream channels to the user's set top box. This arrangement isparticularly suited for use with the preferred embodiment disclosed inthe '603 patent where channel hyperlink requests are sent to the headendvia an upstream channel, or other communications link. When ahyperlinking request is received from a set top, processing equipment inthe headend accesses the content related information, and combines itwith a reduced, scaled version of the video programming that the userwas viewing at the time the hyperlink request is sent. This combinedinformation is then sent to the user's set top on one of the downstreamchannels. In the case of a content related web page, the set top willdisplay the web page on the user's television or monitor with a reducedsize image of the associated television program overlaid on a portion ofthe page. Alternatively, the size of the web page can be reduced so thatthe web page is overlaid on a full size television program. Thus, thisalternative embodiment of the invention also provides picture-in-picturecapability without the need for more than one tuner in the set top, andwithout the requirement that the additional image information be sentseparately from the video program information.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The features and advantages of the present invention will becomeapparent from the following detailed consideration of a preferredembodiment thereof, taken in conjunction with the accompanying drawingfigures, in which:

[0016]FIG. 1 is a block diagram of a CATV system that is constructed inaccordance with the preferred embodiments of the present invention;

[0017]FIG. 2 is a block diagram of a cable headend that is employed inthe system of FIG. 1; and

[0018]FIG. 3 is a block diagram of a set top converter box that isemployed with the system of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Turning now to a detailed consideration of a number of preferredembodiments of the present invention, FIG. 1 is a general block diagramof a CATV system 10 which incorporates elements for facilitating accessand broadcast of Internet web pages and other information to a pluralityof system users. The system 10 is illustrative of one type of systemwith which the concepts of the present invention may be employed. Itshould be noted that the CATV system 10 is illustrated in general formsince many of its detailed elements are not necessary for anunderstanding of the present invention.

[0020] The CATV system 10 includes a cable headend 12 and a cabletelevision distribution network 13 for interfacing the headend 12 to aplurality of terminal devices, which are preferably set top converterboxes 14 (set tops), but could be any other suitable receiving andprocessing device. A plurality of transmission links 15 interconnectsthe set tops 14 with the distribution network 13. Each of the links 15is illustrated as being bi-directional with a plurality of downstreamchannels 16 and one or more upstream channels 17. The upstream channel17 can be used, for example, for sending information from the set tops14 to the headend 12, such as two-way channel hyperlinking requests inaccordance with the method set forth in the '603 patent.

[0021] The cable headend 12 receives video programming andInternet-based and other information from remote sources (not shown),and transmits the video programming and other information through thedistribution network 13 to the set tops 14. Alternatively oradditionally, the information may be stored in one or more localdatabases 18 in, or interfaced to, the headend 12. The information cancomprise many types of information, for example, television programminginformation, user account information, and advertisements.

[0022] Each of the set tops 14 is interfaced via a number ofcommunication links 19 (e.g., cables, infrared wireless links, etc.) toa television or monitor 20 for displaying the received video programmingand other information, and one or more input devices, such as a wirelesskeyboard 22 and a remote controller 24, for user interaction with theset top 14.

[0023] The details of the elements in the headend 12 are illustrated inFIG. 2. Typically, the video programming that is received by the headend12 is in either an analog format, or a digitally compressed or encodedformat, such as MPEG 1 or MPEG 2. The Internet-based information, on theother hand, is typically HTML coded web pages along with still imagescoded in JPEG or GIF formats. The web pages are generated either by aweb page generator 25 located in the headend 12, or by a web pagegenerator at a remote location. As set forth in the '603 patent, theCATV system 10 allows a system user that is a subscriber to an Internetaccess service, to conduct an Internet session by sending appropriatecommands via the keyboard 22 and/or remote controller 24 to a processor26 in the headend 12. The headend processor 26 processes a hyperlinkrequest by accessing a hyperlink database 27 that is either located in,or interfaced to, the headend 12, and retrieving a URL for the web pageto be downloaded. The headend processor 26 then connects the user to oneof a plurality of browser applications 28, retrieves the requestedInternet information from the remote source or the local database 18,and downloads the information to the user's set top 14 for display ontheir television or monitor 20. In addition, the first preferredembodiment of the present invention also includes the capability ofprocessing hyperlink and other Internet access requests in each of theset tops 14. As will be shown, this is made possible by continuallybroadcasting any number of Internet web pages from the headend 12, andproviding the set tops 14 with channel and time slot information foreach of the web pages. In this instance, the web page data is suppliedto the browser applications 28, one for each web page to be broadcast,to generate web page bit map images to be broadcast to system users.

[0024] Preferably, additional data is added by the web page generator 25(or by a remotely located web page generator) to the usual encoded imagedata to indicate relationships between the channels and which keysequences are to be used to select which channels. This data compriseslinkage commands that are used to traverse the broadcast channels bymenu instead of by channel, and to hyperlink to web pages fromhyperlinks embedded in the broadcast channels. Though similar to tuningto a channel from a set top-resident channel guide, this differs in thatthe tuning would not be to a channel, but to a content stream and wouldbe more like hyperlinking among web pages. Also, when broadcasting toset tops that can access the channel hyperlinking service disclosed inthe '603 patent, the pages can provide links that function as access tothis service.

[0025] To facilitate insertion of the linkage commands in the HTML webpage data, the web page generator is preferably provided with a plug-inreferred to as a linkage editor 29. The browser applications 28 are ableto accept the linkage commands and generate data in the broadcast streamthat would specify to set tops 14 the linkage commands on the currentpage.

[0026] An Internet session manager 30 is provided which starts thebrowser applications 28 and a display manager 32. The browserapplications 28 and display manager 32 are interfaced to acommunications manager 34 to facilitate downloading of the web pages tothe system users. A video encoder 36, which may be an MPEG 1 or MPEG 2encoder, for example, is also preferably provided in the headend 12 forencoding the web page bit map images before they are transmitted by thedistribution network 13 to the set tops 14. The encoder 36 is employedto reduce the bandwidth necessary to transmit the data generated by thebrowser application 28, and to generate, for example, an MPEG standardcompliant video stream.

[0027] From the encoder 36, the web page data for each of the web pagesis passed through one or more digital multiplexers 38, each of whichcombines a plurality of the web pages into a single data stream that isfed to the distribution network 13 for broadcast on a correspondingdigital one of the downstream channels 16. Each of the multiplexers 38act as a carousel by employing a time division multiplexing scheme inwhich the data for each web page is assigned a time slot in a multipletime slot, repeating sequence. The number and length of slots in thesequence is selected based on the type and amount of information to besent. In the event that the information is the HTML data for a staticweb page, then it is sufficient to send this data only once every 10seconds or so, since each set top 14 need only receive the data once.

[0028] In one embodiment of the invention for implementingpicture-in-picture graphics presentation without the need for multipletuners, one or more scaler applications 39 are provided in the headend12 for selectively reducing the size of either the video programmingimages or the web page images, so that one may be overlaid on the other.As is well known, a picture-in-picture format displays information inwindows on a television screen that are a fraction of the size of anentire display screen. The reduced size and resolution ofpicture-in-picture images require less image data to be transmitted, andless bandwidth utilized, than is required to display a full screenimage. In this embodiment of the present invention, the resulting excessbandwidth is utilized to transmit one or more overlays of informationwith the reduced image for display on a single television screen. Suchoverlays may include, but are not limited to, additional full motionvideo programs, web pages retrieved from the Internet, advertisementsand television programming information.

[0029] The scaler applications 39 receive the incoming video programmingor the web pages from the remote or local sources, and reduce the sizeof the video images by a predetermined amount before they are fed to onethe encoders 36. The scaled and encoded video or other images are thenmultiplexed by one or more of the multiplexers 38, and may be combinedwith the other image information. As previously stated, with the adventof true interactive television, the present invention permits a user tosimultaneously view a television program and conduct an Internet sessionutilizing a television with a single tuner. As information is retrievedby one of the browser applications 28, it is either encoded andmultiplexed with the scaled and encoded video programming, or it isencoded, scaled and multiplexed with the video programming. The encodedand multiplexed data stream is then distributed via the distributionnetwork 13 to the set top 14. The data stream may thus be displayed in apicture-in-picture format even where the set top 14 contains no scalingmeans and the system maintains a single tuner.

[0030] With reference to FIG. 3, the details of one of the set tops 14are illustrated. A tuner 40 is provided for receiving the digitallyencoded or compressed video programming and Internet-based informationfrom the distribution network 13 on each of the downstream channels 16,and selecting the one of the downstream channels 16 from whichinformation will be displayed on the television or monitor 20. From thetuner 40, the selected information passes through a decoder 42 whichrestores the video programming signals and web page image data to theiroriginal form for display on the television or monitor 20. The decoder42 is of the same format as the encoder 36, such as MPEG 1 or MPEG 2,for example. In the case of a two-way system, an upstream transmitter 43is also provided for transmitting hyperlink requests and otherinformation to the headend 12 via the upstream channel 17.

[0031] The heart of the set top 14 is a terminal processor 44 thatcontrols operation of the tuner 40 in response to requests received byan input receiver 45 (e.g., an infrared receiver) from the user via thekeyboard 22 or remote controller 24. The terminal processor 44 isinterfaced to a channel mapping database 46 that is contained in amemory 48, and stores channel mapping and hyperlink requestidentification information for any number of user selectable channelhyperlinks or assessable web pages or sites. For example, the user mayactuate the hyperlink button on their remote controller 24 during anews, weather or sports television broadcast, and the terminal processor44 will access the channel mapping database 46 to identify the hyperlinkrequest, and determine on which of the downstream channels 16, and inwhich time slot or PID, related Internet based information (e.g., news,weather or sports web site) is being broadcast.

[0032] The terminal processor 44 determines the identity of thehyperlink using the linkage commands that are inserted by the linkageeditor 29 at the headend 12. More particularly, an input application 49is run by the terminal processor 44 that processes inputs received bythe input receiver 45 by detecting when either the channel hyperlinkbutton on the keyboard 22 or remote controller 24 has been pressed, orwhen a hyperlink button on a currently displayed image has beenhighlighted and selected by the user. Once the hyperlink request andcorresponding channel and time slot information have been identified,the terminal processor 44 will then instruct the tuner 40 to switch tothe designated channel so that the requested information can bedownloaded into the set top 14 for display by a terminal display manager52 on the user's television or monitor 20. A cache 50 can be provided inthe memory 48 for pre-storing downloaded information if desired. Tofacilitate downloading of channel mapping and hyperlink requestidentification information from the headend 12 to the channel mappingdatabase 46, an out-of-band tuner 54 can be provided that can also beused for transmission of signaling information, as is conventional.Alternatively, the channel mapping and hyperlink request identificationinformation can be downloaded through one of the downstream channels 16for reception by the in-band tuner 40.

[0033] In another embodiment of the invention for facilitatingpicture-in-picture capability using the single in-band tuner 40, theterminal processor 44 controls the tuner 40 in the following manner. Forexample, when the user enters a channel hyperlink request (e.g., bypressing the channel hyperlink button on the remote controller 24), thetuner 40 is instructed by the terminal processor 44 to briefly tune awayfrom the television program to the appropriate data channel forreceiving the hyperlink information. Any web pages or other informationassociated with the hyperlink are downloaded and stored in the set top'scache 50, and then the tuner 40 automatically tunes back to thetelevision program. The user can then interact with the hyperlinkcontent and continue watching the television program simultaneouslyusing any suitable picture-in-picture graphics application that isprogrammed into the display manager 52.

[0034] To minimize the amount of time that the user cannot watch theirprogram, the time-map of the channel hyperlink content that is stored inthe channel mapping database 46 is employed by the terminal processor 44to delay tuning off of the video channel until the data of interestappears in the multiplexer 38 at the headend 12, and is about to bebroadcast. For example, if the multiplexer carousel is ten seconds longand the user presses the hyperlink button, there may be as much as a tensecond wait for the data to appear in the carousel. Without using thetime mapping information, and assuming a one second tuning time, theuser would miss an average of eight seconds of their television programwhen pressing the channel hyperlink button (one second to tune to datachannel, average of five seconds for data to come around in thecarousel, one second to collect and process the data, and one second totune back to video programming). However, by using the time mappinginformation, this delay can be reduced to three seconds: one second totune the data channel, one second to collect and process the data andone second to tune back to the television program.

[0035] In the preferred embodiments of the present invention, a numberof additional features are preferably employed. One feature involves theencoding procedure implemented by the encoder 36. To encode the web pageimage bit map data generated by the browser applications 28, the encoder36 employs any known conventional algorithm for encoding motion picturevideo frames, such as MPEG 1 or MPEG 2. The first frame is encoded as anintra or I frame where information for all of the pixels in the frameneeds to be transmitted since no previous frame information isavailable. In a hyperlinking application where a specific user isreceiving web page data, the next frame in the sequence can then beencoded either as an P (predictive) frame or a B (bi-directionalpredictive-coded) frame which includes only the difference or motionvector data resulting from the frame comparisons. P or B frames cancontinue to be used for encoding the succeeding frames in the sequenceuntil a substantial change, such as a scene change, occurs, thusnecessitating formation of another I frame. The use of P or B framessubstantially reduces bandwidth requirements since considerably lessdata has to be transmitted.

[0036] However, the foregoing technique is preferably modified in theembodiment of the present invention where web pages are continuallybroadcast on a selected channel to all system users. In this instance,it is preferable that the encoder 36 transmit a full I-frame frequentlyenough (e.g., once every second) that any of the set tops 14 which tuneto the channel get an I-frame within a short enough time period that theviewer is satisfied with the service. Further, with this broadcastservice, the stream must be constantly generated since the stream offersno feedback indicating how many of the set tops 14 are viewing the cablechannel (stream) or when a set top tunes to or from a cable channelcarrying the stream.

[0037] The headend communications manager 34 and its configuration arealso preferably modified so that the configuration file can specify thata downstream channel is a broadcast channel, and will also specify achannel number that will be used when the communications manager 34establishes an Internet session with the Internet session manager 30.That channel number is used to access an initial URL from thehyperlinking database 27. Whenever the communications manager 34 doesnot have an Internet session associated with the broadcast channel, thecommunications manager 34 establishes a session with the session manager30. To do this, the communications manager 34 generates a hyperlinkinglogin using the configured channel. The URL from the hyperlinkingdatabase 27 will be the first page displayed on the broadcast channel.That page may be the only page or may be one of a series of pagesdisplayed at intervals (current HTML can step through the series ofpages).

[0038] The broadcasting embodiment of the system 10 thus facilitatesbroadcast of web pages and other information over a group of channels toall users of the system 10, regardless of whether they are subscribersto an Internet access service offered by the cable company. This designnot only supports the broadcast of static web pages, but support seriesof web pages and animated web pages. The system 10 can be used tobroadcast several channels containing such diverse pages as stockticker/news, headline news/sports, scrolling/paging detail reports,program guide information, weather and advertising. On a simple systemthe pages would be virtually unrelated, though they could suggest tuningto another channel for more details on stories. On a more advancedsystem, the pages could contain instructions to the set tops 14 so thatpressing key sequences would automatically tune to the details.

[0039] The picture-in-picture embodiments of the invention permitrequested information to be simultaneously displayed along with a videoprogram, for example, that a user is currently viewing. As an example,in a two-way application, if a user sends a hyperlink request to theheadend 12, the headend processor 26 will retrieve the requestedinformation, e.g., web page, start one of the browser applications 28,combine the web page information with a reduced size version of thevideo program that the user is currently viewing by first applying theprogram to the scaler application 39, and download the combinedinformation stream on one of the downstream channels 16. The set topprocessor 44 will then be instructed to switch the tuner 40 to thatchannel. In the one-way broadcasting embodiment, the same result isachieved by first downloading the web page information into the settop's cache 50, and then combining the stored information with thereceived video program using a picture-in-picture application in the settop display manager 52.

[0040] Although the invention has been disclosed in terms of a number ofpreferred embodiments and variations thereon, it will be understood thatthe scope of the invention as defined by the following claims is notlimited thereto. For example, the preferred embodiments are directed toa cable television distribution network having Internet accesscapabilities. However, the concepts of the present invention can beapplied to any type of networked broadcast distribution system that iscapable of accessing or hyperlinking to any type of additionalinformation.

1. A system for broadcasting information over a television distributionnetwork comprising: a) a network headend for accessing information fromone or more sources, and broadcasting said information; b) a pluralityof downstream channels interfaced to said headend for transmitting saidinformation; and c) a plurality of terminal devices for receiving saiddownstream channels, each said terminal device including: 1) a tuner forreceiving and selecting said downstream channels; and 2) a terminalprocessor for receiving channel selection and information requests froma user, and instructing said tuner to select one of said downstreamchannels, said terminal processor including programming for receiving aninformation request from a user, and in response thereto, instructingsaid tuner to select one of said downstream channels on which saidrequested information is being transmitted from said headend.
 2. Thesystem of claim 1, wherein said terminal device further includes amemory containing a channel mapping database for identifying, for eachof a plurality of possible information requests received from a user, aone of said channels on which said requested information is beingtransmitted from said headend.
 3. The system of claim 2, wherein saidheadend further includes at least a first multiplexer for multiplexing aplurality of information data streams on one of said downstreamchannels, each of said information data streams containing informationidentified by a corresponding one of said plurality of informationrequests; and said channel mapping database further includes timinginformation identifying a time slot in a multiple time slot sequencewhen each of said information data streams is to be transmitted.
 4. Thesystem of claim 3, wherein said terminal processor is further programmedto identify from said channel mapping database, a time at which said oneof said information data streams containing said requested informationis to be transmitted on said one of said downstream channels, and forinstructing said tuner to select said one of said downstream channels atsaid time.
 5. The system of claim 2, wherein said terminal devicefurther includes a memory for storing said information data streams, anda display manager for formatting said information for display on a videomonitor interfaced to said terminal device.
 6. The system of claim 5,wherein said display manager further includes a picture-in-pictureapplication for simultaneously displaying first information stored insaid memory, and second information being received on one of saiddownstream channels.
 7. The system of claim 1, wherein said headendfurther includes an encoder for digitally encoding information datastreams to be broadcast and said terminal device further includes adecoder for decoding said information data streams, said encoder beingprogrammed to generate a full image frame periodically to facilitatesynchronization of said decoder with said encoded data stream.
 8. Thesystem of claim 1, wherein said requested information comprises Internetweb page data, said web page having content that is related to a videoprogram that is being received by said tuner at a time that saidinformation request is received by said terminal processor.
 9. Thesystem of claim 1, further including an input device for enteringinformation requests into said terminal processor either throughactuation of a button on said input device, or selection of an on-screenbutton displayed on a video image.
 10. A terminal device for receivinginformation transmitted on a plurality of downstream channels in atelevision distribution system, and formatting said information fordisplay on a video display device, said terminal device comprising: a) atuner for receiving and selecting said downstream channels; b) a memoryfor storing channel mapping and information request identificationinformation; and c) a processor for receiving an information requestfrom a user, said processor being programmed, in response to receipt ofsaid information request, to access said memory to identify firstinformation specified by said request, determine a first of saidchannels on which said first information is to be transmitted, and causesaid tuner to select said first of said channels to receive said firstinformation.
 11. The terminal device of claim 10, wherein said processoris further programmed to download said first information into a cache insaid memory, and then instruct said tuner to select a second of saidchannels that is transmitting second information that was being receivedwhen said information request for said first information was received bysaid processor.
 12. The terminal device of claim 11, further comprisinga display manager for formatting first images corresponding to saidfirst information stored in said memory and second images correspondingto said second information in a picture-in-picture format forsimultaneous display on a display device interfaced to said terminaldevice.
 13. The terminal device of claim 10, wherein said channelmapping database contains information that maps each of a plurality ofpossible information requests to one of said downstream channels onwhich corresponding information is to be transmitted.
 14. The terminaldevice of claim 13, wherein said channel mapping database furtherincludes time slot information identifying a time slot in a multiplexeddata stream in which information corresponding to each informationrequest is to be transmitted.
 15. The terminal device of claim 14,wherein said processor is further programmed to instruct said tuner toselect said first channel just prior to transmission on said firstchannel of said first information in said multiplexed data stream. 16.The terminal device of claim 10, further including a second tuner fordownloading channel mapping and information request identificationinformation into said channel mapping database.
 17. The terminal deviceof claim 10, wherein said device is a set top converter box forreceiving a plurality of cable television channels.
 18. The terminaldevice of claim 17, wherein said information request comprises a requestfor Internet-based information that is related to a content of a videoprogram that is being received by said tuner when said informationrequest for information is received by said processor.
 19. The terminaldevice of claim 10, wherein said information request comprises a requestfor information selected from the group comprising Internet-basedinformation, program guide information and user account information. 20.The terminal display device of claim 10, further including a wirelessreceiver for receiving information requests from a wireless inputdevice.
 21. A method for requesting and receiving information in atelevision distribution network comprising: a) providing a networkheadend for accessing information from one or more sources, andbroadcasting said information; b) providing a plurality of downstreamchannels interfaced to said headend for transmitting said information;c) providing a plurality of terminal devices interfaced to saiddownstream channels for receiving information on said channels, andformatting said information for display on a display device, each saidterminal device including a tuner for receiving and selecting saiddownstream channels, and a terminal processor for receiving informationrequests from a user, and instructing said tuner to select one of saiddownstream channels; d) receiving a request for information in saidterminal device from an input device; e) identifying a one of saiddownstream channels on which said information is to be transmitted; f)causing said tuner to select said one of said downstream channels; andg) receiving said requested information with said terminal device. 22.The method of claim 21, wherein said terminal device further includes amemory containing a channel mapping database for identifying, for eachof a plurality of possible information requests received from a user, aone of said channels on which said requested information is beingtransmitted from said headend, and said step of identifying a one ofsaid downstream channels on which said information is to be transmittedcomprises accessing said channel mapping database to identify saidchannel from said information request.
 23. The method of claim 22,wherein said terminal processor further identifies from said channelmapping database, a time at which said requested information is to betransmitted on said one of said downstream channels, and said step ofcausing said tuner to select said one of said downstream channels,further comprises causing said tuner to select said one of saiddownstream channels at said time.
 24. The method of claim 21, furthercomprising the step of: h) storing said requested information in amemory in said terminal device.
 25. The method of claim 24, furthercomprising the steps of: i) after said requested information is storedin said memory, causing said tuner to select a second of said channelsto which said tuner was tuned when said information request was receivedby said terminal processor, said second of said channels transmitting asecond information stream; j) formatting said requested information andsaid second information stream into a combined picture-in-picture imagedata stream; and k) supplying said image data stream to a displaydevice.
 26. The method of claim 21, further comprising the steps ofencoding information in said headend to be broadcast to form a pluralityof encoded data streams, said encoding including periodic generation ofa full image frame, and decoding said encoded data streams in saidterminal device.
 27. The method of claim 21, wherein said requestedinformation comprises Internet web page data, said web page havingcontent that is related to a video program that is being received bysaid tuner at a time that said information request is received by saidterminal processor.
 28. The method of claim 21, wherein the step furtherof receiving a request for information in said terminal device from aninput device, further includes entering said request either throughactuation of a button on said input device, or selection of an on-screenbutton displayed on a video image.
 29. A terminal device for receivingmultiple information streams and forming a picture-in-picture imageinformation stream therefrom comprising: 1) a tuner for receiving andselecting a plurality of channels, each of said channels transmittingone or more information streams; 2) a terminal processor for instructingsaid tuner to select one of said downstream channels; 3) a memory forstoring information received on said downstream channels; and 4) adisplay manager having a picture-picture graphics application forretrieving information stored in said memory, and combining it with aninformation stream that is being received by said tuner on one of saiddownstream channels to form a picture-in-picture image data stream forsimultaneous display of said stored information and said informationstream on a display device interfaced to said terminal device.
 30. Amethod for receiving multiple information streams and forming apicture-in-picture image data stream therefrom comprising the steps of:a) providing a terminal device having a tuner for receiving andselecting a plurality of channels, each of said channels transmittingone or more information streams; b) receiving a first information streamon one of said channels; c) storing said first information stream in amemory in said terminal device; d) receiving a second information streamon one of said channels; e) combining said first information stream withsaid second information in a picture-in-picture format to form acombined image data stream; and f) supplying said combined imageinformation stream to a display device for simultaneous display ofimages corresponding to said first and second information streams.
 31. Anetwork headend for accessing information from one or more sources, andbroadcasting said information over a television distribution network,said headend comprising: a) at least one scaler for receiving a firstimage generating information stream and generating a scaled version ofsaid first information stream having a reduced image size; and b) atleast one multiplexer for combining said scaled version with a secondimage generating information stream to form a combined informationstream, said combined information stream being formatted in apicture-in-picture format where a first image generated by said firstimage generating information stream is overlaid on a second imagegenerated by said second image generating information stream.
 32. Theheadend of claim 31, further including an encoder for encoding saidscaled version prior to being combined with said second informationstream.
 33. The headend of claim 31, wherein said first informationstream is a video program, and said second information stream isselected from the group comprising an Internet web page, a televisionprogram guide and user account information.
 34. The headend of claim 33,wherein said second information stream comprises an Internet web pagethat is related to a program content of said video program.
 35. A methodfor transmitting multiple information streams in a networkeddistribution system comprising the steps of: a) providing a first imagegenerating information stream; b) scaling said information stream toform a reduced size image generating information stream; c) combiningsaid reduced size image information stream with a second imageinformation stream in a picture-in-picture format to form a combinedimage information stream; and d) transmitting said combined imageinformation stream through a distribution network.
 36. The method ofclaim 35, wherein the steps of scaling and combining are carried out inresponse to a request received from a terminal device for said secondinformation stream, and said step of transmitting further comprisestransmitting said combined image information stream to said terminaldevice.
 37. The method of claim 35, wherein said first informationstream is a video program, and said second information stream isselected from the group comprising an Internet web page, a televisionprogram guide and user account information.
 38. The method of claim 37,wherein said second information stream comprises an Internet web pagethat is related to a program content of said video program.